Phase 5 Weapon Systems Inc Revolving Sling Attachment Solution Black. The REVO also has patented technology developed to internally limit the amount of rotation and eliminates external obstruction issues completely. The REVO-SAS is machined from billet steel for maximum strength and durability. REVO IS NOT A QD SWIVEL ATTACHMENT POINT. Specifications for Phase 5 Weapon Systems Inc Revolving Sling Attachment Solution: Manufacturer: Phase 5 Weapon Systems Inc Color: Black Fabric/Material: Billet Steel Finish: Mil-Spec Phosphate Included Accessories: Castle Nut Features of Phase 5 Weapon Systems Inc Revolving Sling Attachment Solution: Patented construction technology Phase 5 custom-machined proprietary castle nut included Billet steel construction - Rugged material allows for maximum strength and durability Mil-Spec phosphate finish - Ensures aesthetic uniformity and stays true to military standards of material coating Included Accessories: Castle Nut (Specific to product) Package Contents: Phase 5 Weapon Systems Inc Revolving Sling Attachment Solution Castle Nut (Specific to product) Phase 5 Weapon Systems Inc REVO: Revolving Sling Attachment Solution Black